In-molded capacitive switch

• US 8,514,545 B2
• Filed: 04/18/2008
• Issued: 08/20/2013
• Est. Priority Date: 04/20/2007
• Status: Active Grant

• Current Assignee: E2IP Technologies Incorporated
• Original Assignee: Ink-Logix, LLC
• Inventors: Haag, Ronald H.
• Primary Examiner(s): Sinclair, David M
• Application Number:
  US12/106,250
• Publication Number:
  US 20080257706A1
• Time in Patent Office: 1,950 Days
• Field of Search: 200/18, 200/600, 361/277, 361/283.1, 361/280
• US Class Current: 361/280
• CPC Class Codes: B29C 45/14655 connected to or mounted on a carrier, e.g. lead frame
• CPC Class Codes: B29C 45/14811 Multilayered articles B29C45/14827 takes precedence
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 2217/96019 using conductive paint
• CPC Class Codes: H03K 2217/960755 Constructional details of capacitive touch and proximity switches
• CPC Class Codes: H03K 2217/960785 with illumination
• CPC Class Codes: H03K 2217/96079 using a single or more light guides
• CPC Class Codes: H05K 2203/1316 Moulded encapsulation of mounted components
• CPC Class Codes: H05K 3/0014 Shaping of the substrate, e.g. by moulding
• CPC Class Codes: H05K 3/12 using thick film techniques, e.g. printing techniques to apply the conductive material or similar techniques for applying conductive paste or ink patterns
• CPC Class Codes: H05K 3/284 for encapsulating mounted components H05K1/185 takes precedence
• CPC Class Codes: H05K 3/30 Assembling printed circuits with electric components, e.g. with resistor
• CPC Class Codes: Y10T 29/49105 Switch making
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

An article of manufacture having an in-molded capacitive switch and method of making the same are shown and described. In one disclosed method, a conductive ink sensing zone is printed on a film. The film is formed to a desired shape and put in an injection mold. A molten plastic material is introduced into the injection mold to form a rigid structure that retains the film.

Claims

1. An article of manufacture having an in molded capacitive switch, comprising:

a thermo-formable plastic film having a surface;

at least one printed thermo-formable graphical layer on the surface of the thermo-formable plastic film;

at least one printed thermo-formable conductive ink layer on the surface of the thermo-formable plastic film or on the thermo-formable graphical layer;

at least one thermo-formable dielectric layer on the printed thermo-formable conductive ink layer;

at least one conductive ink layer sensing zone printed on the dielectric layer surface; and

a molded plastic support structure, wherein the surface of the thermo-formable plastic film faces the molded plastic support structure, and the thermo-formable plastic film is secured to the plastic support structure to form a substantially rigid structure, and wherein the capacitive switch is adapted to be selectively operated as a sensing zone by a user upon placement of an object proximate to or in contact with the switch; and

wherein at least a portion of the surface of the film is exposed.

2. The article of manufacture of claim 1, wherein the at least one conductive ink layer is not exposed.

3. The article of manufacture of claim 1, wherein at least a portion of the surface of the film is not exposed.

4. The article of manufacture of claim 1, further comprising at least one connector electrically connected to the at least one conductive ink layer, wherein a portion of the at least one connector projects away from the plastic support structure.

5. The article of manufacture of claim 4, wherein the film further comprises at least one printed ink electrode electrically connected to the at least one conductive ink layer, and wherein the at least one connector is connected to the at least one printed ink electrode with a conductive adhesive.

6. The article of manufacture of claim 1, comprising at least one electrical connector molded into the plastic support structure and electrically connected to the at least one conductive ink layer.

7. The article of manufacture of claim 1, further comprising at least one light emitting diode formed into the plastic support structure such that when energy is applied to the diode, it emits light from the front surface of the film.

8. The article of manufacture of claim 1, further comprising indicia related to a function of the capacitive switch, wherein the indicia is printed on another surface of the film and is visible on the surface of the film.

9. A control device, comprising:

the article of manufacture of claim 1, wherein the at least one conductive ink sensing zone is electrically connected to a circuit that is operable to detect capacitance changes.

10. An electromagnetic shield, comprising:

a thermo-formable plastic film having a thermo-formable conductive ink ground layer printed on a surface of the thermo-formable plastic film, the thermo-formable conductive ink ground layer formed to define apertures that are sized to accommodate one or more sensing zones formed from thermo-formable conductive ink; and

a molded plastic support structure, wherein the surface of the thermo-formable plastic film faces the molded plastic support structure and is bonded to the plastic support structure to form a substantially rigid structure, and

wherein the surface of said film is the A-surface.

11. The electromagnetic shield of claim 10, wherein the film is molded within the plastic support structure.

12. The electromagnetic shield of claim 11, wherein some of the A-surface of said film is exposed.

13. A capacitive switch, comprising:

a thermo-formable plastic film having one or more thermo-formable conductive ink layers forming a sensing zone printed on a surface of the thermo-formable plastic film, the sensing zone allowing selective activation of the capacitive switch by placement of an object proximate the switch;

a molded plastic support structure, wherein the thermo-formable plastic film is bonded to the plastic support structure to form a substantially rigid structure;

at least one thermo-formable dielectric ink layer applied adjacent to said conductive ink sensing zone; and

at least one thermo-formable conductive ink layer adjacent to said dielectric ink layer, wherein the dielectric ink layer insulates said conductive ink layer from said conductive ink sensing zone, and

wherein the surface of said film is the A-surface.

14. The capacitive switch of claim 13, wherein the film is molded within the plastic support structure.

15. The capacitive switch of claim 14, wherein some of the A-surface of said film is exposed.